Today's news numbs us with accounts of kidnapping and theft. Even the most hardened cynics are haunted by the stories of child abductions: a stranger dragging a child from her home, adolescents taking a screaming toddler from a shopping mall, infants kidnapped from a hospital. Constant vigilance, and fear, have become all to common place for parent and child alike.
Those solutions that have been offered in the past are of limited effectiveness, or as a practical matter unavailable to the average person. Child monitoring devices, such as described in U.S. Pat. No. 4,899,135, have a limited range, and once a child is beyond that range provides no means for relocating the child. Emergency locator systems, such as shown in U.S. Pat. No. 5,021,794, provide a means for homing in on a child from a greater range, but also require the additional assistance of mobile homing units and remain ineffective beyond a still limited broadcasting range of the homing beacon.
While there are technologies offering better location methods, these remain mostly out of reach of the average person due to the cost prohibitive nature of the solution. Thus, while RF tags installed on vehicles permit the location of stolen automobiles, the transmitters for such tags require high power sources (car batteries), are relatively expensive (currently over five hundred dollars), and require the intervention of local police with additional hardware and software (at more expense) for tracking the car. Emergency systems, such as that described in U.S. Pat. No. 5,218,367, represent similarly expensive solutions, relying upon an on board emergency activation circuitry and a high power source for the continuous multicell control signal scan and the response transmissions thereto. Likewise, any system incorporating a GPS (Global Positioning System) receiver will, although providing accurate location information, add undesirable bulk and several hundred dollars expense to the locator device.
Any solution to this need for inexpensive locator devices should also be balanced against the right to privacy in our own personal affairs. Safeguards must exist against unwanted third party (listening) in on others' locations. Thus, while any effective solution will provide an inexpensive locating system, it should also include subsystems to ensure that only those persons authorized to follow the movements of a locator device will in fact have access to the location information.
Finally, it is also desirable that any such solution provide the location information without requiring the intervention of our already overtaxed emergency services, except where necessary.